Discharge container

ABSTRACT

The container of this invention is a squeezable laminated container of the delaminatable type in which the layers can be easily broken away from each other. The container comprises the first check valve fitted to the neck and has an opening in the bottom plate. The base cup comprises the second check valve, and is fitted tightly around the container bottom cylinder. In this discharge container, it is sought to secure stable and strong fitting and to maintain tight contact stably, between the container and the base cup.  
     The container  1  is a squeezable and delaminatable bottle and is provided with a seal on the bottom cylinder  8 . The neck  6  of the container  1  is opened or closed by the first check valve  18 , and an opening  15  is formed in the outer layer  2  of the bottom cylinder  8  so that the opening  15  can be used as a port to introduce outside air into the interspace between the outer layer  2  and the inner layer  3 . The base cup  20  is provided with the second check valve  27 , which opens or closes the air intake hole  25  that has been opened in the cup bottom plate. This base cup  20  is tightly screwed on the container bottom cylinder  8 , and a combination of seals closes the interstice between the container  1  and the base cup  20 . The seals are disposed near the lower overhang  11 , which serves as reinforcement for the peripheral bottom wall  9  of the bottom cylinder  8 . Thus, it is possible to enhance the shape-holding property by means of the wall structure comprising many projecting ridges on the walls and to accomplish tight fitting between the container and the base cup.

TECHNICAL FIELD

This invention relates to a discharge container capable of dischargingthe contents without allowing outside air to enter the inside of thecontainer, and in particular to a discharge container comprising asqueezable container and a base cup, with the container comprising anouter layer molded in a definite shape and laminated with an inner layerin a peelable manner, and the base cup being fitted tightly around thebottom cylinder of the container.

BACKGROUND ART

Prior to this invention, the applicant of this invention filed anapplication for patent (See patent document 1). That invention relatedto a discharge container comprising a squeezable container having anouter layer, an inner layer laminated with the outer layer in a mannerthat the inner layer is peelable from the outer layer, a container neckdisposed on top of this squeezable container and used to form adischarge port for the contents, and an opening disposed in a part ofthe outer layer located in the bottom plate of bottom cylinder and usedto introduce outside air into the interspace between the outer layer andthe inner layer; and also comprising the first check valve used to openor close the neck of the squeezable container so as to prevent thebackflow of the contents into the container and the inflow of outsideair, a base cup tightly fitted around the bottom cylinder and having anair intake hole disposed in the cup bottom plate, and the second checkvalve fitted to the air intake hole of the base cup to permit outsideair to pass through the air intake hole.

[Patent document 1] P2002-129195 patent specification

In the above-described conventional art, the container bottom has stablestrength and a self-standing function because the base cup serves toreinforce the container bottom. However, if the squeezability of thecontainer is enhanced in response to an increasing request for resourcessaving, the container tends to be much more deformable. Depending on theextent of deformability, there is a fear that the firm fitting strengthand reliable sealing property may decrease between the container and thebase cup.

DISCLOSURE OF THE INVENTION

The means of carrying out the invention of Claim 1 to solve theabove-described technical problem exists in the configuration that thedischarge container comprises:

-   a squeezable container, which has an outer layer and an inner layer    that are laminated to each other in a manner that the inner layer is    peelable from the outer layer, a neck disposed in the upper portion    of the container to form a discharge port through which the contents    are discharged, and an opening disposed in a part of the outer layer    at a position in the bottom plate of container bottom cylinder so as    to introduce outside air into the interspace between the outer layer    and the inner layer;-   the first check valve, which opens or closes the opening to prevent    the contents from flowing back into the container and to inhibit the    inflow of outside air;-   a base cup in a bottomed cylindrical shape, which has a cylindrical    wall that comes in screw engagement with the container bottom    cylinder and also has an air intake hole opened in the cup bottom    plate; and-   the second check valve fitted to the air intake hole to permit    outside air to enter the interspace between layers,-   wherein airtight fitting of peripheral bottom wall of the container    to the cylindrical wall of the base cup is accomplished by tight    contact between the first seal disposed on the peripheral bottom    wall of the bottom cylinder and the second seal disposed on the back    of the cylindrical wall.

In the invention of Claim 1, the body of the squeezable container issqueezed to open the first check valve that has closed the neck. Then,the contents are discharged out of the container through the neck.

The discharge of the contents comes to a halt as soon as the pressure isreleased. The outer layer begins restoring its original shape because ofits own resilient recovering force. The first check valve acts to closethe neck and to prevent the inflow of outside air and the backflow ofthe contents into the container.

At that time, the inner layer has a reduced capacity and remainsdeformed with the decrease in the contents. As a result, pressurereduction takes place in the interspace between the outer layer thatbegins restoring its original shape and the inner layer that remainsdeformed because of a reduced capacity. Under the reduced pressurecondition, the second check valve opens the air intake hole in the basecup to introduce outside air through the opening into the interspacebetween the outer and inner layers. The outer layer quickly returns toits original shape.

After the outer layer has restored its original state, the body of thecontainer can be squeezed again. This second squeeze puts the interspacebetween the outer and inner layers under a pressurized condition. Thispressure is applied on the second check valve to block up the air intakehole, and at the same time, prevents air in the interspace from flowingback and escaping outside.

When the body of the container is squeezed for the second time, thepressure is steadily applied onto the contents inside the deformed innerlayer through the air existing between the outer layer and the innerlayer. As a result, the first check valve again opens the neck of thecontainer to ensure that the contents are discharged from the container.

Even if the opening is disposed in the bottom cylinder of the container,this bottom cylinder of the container is reinforced by the base cup,which is screwed on and fitted around the bottom cylinder of thecontainer. Therefore, the bottom cylinder of the container is stablykept in shape, and the container has the ability to stand alone firmlyunder the configuration that the squeezability of the container isenhanced.

A spiral thread ridge for the screw engagement with the base cup isdisposed on the peripheral bottom wall of the container bottom cylinderon which the base cup is screwed. Since this spiral thread ridge isprepared by corrugating and deforming the peripheral bottom wall, thecorrugated spiral thread ridge serves as a reinforcing rib. Therefore,the base cup remains strongly fitted to the container even if thesqueezability of the container is enhanced.

The container is also provided with the first seal, which is in tightcontact with the second seal of the base cup to ensure that theperipheral bottom wall of the bottom cylinder is tightly fitted to thecylindrical wall of the base cup. Thus, the tight fitting of the basecup to the container is secured.

The invention of Claim 2 includes the means of carrying out theinvention of Claim 1, and additionally comprises that a lower overhangis disposed on the peripheral bottom wall of the container bottomcylinder and that the first seal is disposed at a position near thislower overhang.

In the invention of Claim 2, the first seal is disposed near by thelower overhang and is in tight contact with the second seal of the basecup to ensure that the peripheral bottom wall of the container bottomcylinder is tightly fitted to the cylindrical wall of the base cup. Dueto the reinforcing effect of this lower overhang, the container bottomcylinder keeps its given shape steadily, and further ensures the tightfitting of the base cup to the container.

The invention of Claim 3 includes the means of carrying out theinvention of Claim 1 or 2, and additionally comprises that an opening isformed by cleaving the pinch-off portion that has been formed in theouter layer of the container bottom plate.

Outer-layer parison and inner-layer parison with no mutual compatibilityare co-extruded to obtain laminated parison, which is pressed flat bythe mold pinch-off to give the pinch-off portion. A bottom crack iscleaved easily in this pinch-off portion. In the invention of Claim 3,this crack can be formed in the outer layer of the container bottomplate without any troublesome after-mold processing and can be used asthe opening.

The invention of Claim 4 includes the means of carrying out theinvention of Claim 1 through Claim 3, and additionally comprises thatone of the first seal or the second seal has a peripheral projectingridge structure, with the other one having a smooth peripheral wallstructure.

In the invention of Claim 4, the tight contact of the first seal withthe second seal is in the state of line contact. The tight contact canbe strengthened and stabilized by utilizing local resilient deformation.

The invention of Claim 5 includes the means of carrying out theinvention of Claim 1 through Claim 4, and additionally comprises thateither first seal or the second seal is made of an elastic material in aring shape, and is fitted to the peripheral bottom wall of the containerbottom cylinder or to the cylindrical wall of the base cup.

In the invention of Claim 5, the first seal is in tight contact with thesecond seal through the intermediary of an elastic ring material. Thetight contact can be strengthened and stabilized by utilizing theresilient, deforming force of this material.

The invention of Claim 6 includes the means of carrying out theinvention of Claim 1 through Claim 5, and additionally comprises that acomb attachment to be fitted to the neck comprises a row of combingteeth supported in a line on the comb-back having an internal mainpassage that is connected to the neck of the container. Each tooth hasfront and rear discharge ports opened at a halfway point of the toothheight in the longitudinal direction of teeth and disposed face to facewith opposite discharge ports of the next teeth, and the tooth has alsoa discharge path that connects the discharge ports to the main passage.

In the invention of Claim 6, the body of the container is squeezed withthe container-holding hand. The squeezed container is deformed, and thecontents, a hair dye, are squeezed out directly between teeth. Holdingthe body, the user combs the hair on the head, and at the same time, canapply the discharged hair dye to hair of the head. By squeezing the bodyof the container again, the user is free to squeeze out the hair dyebetween comb teeth so that an adequate amount of the hair dye can beapplied continuously onto hair of the head.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an entire side view of the discharge container in oneembodiment of this invention, with the right half being a verticalsection.

FIG. 2 is a vertical section of the right half of the bottom portionshowing the bottom structure in the embodiment shown in FIG. 1.

FIG. 3 is a bottom plan view taken when the base cup in the embodimentshown in FIG. 1 is cut into a cross-section.

FIG. 4 are enlarged vertical sections of the pinch-off portion of thecontainer bottom plate in the embodiment shown in FIG. 1, in which FIG.4(a) shows the pinch-off portion before the opening is formed, and FIG.4(b) shows the same portion after the opening has been formed.

FIG. 5 is a vertical section of the right half of the bottom portionshowing the bottom structure in another embodiment of this invention.

FIG. 6 is a vertical section of the right half of the bottom portionshowing the bottom structure in another embodiment of this invention.

FIG. 7 is a vertical section of the right half of the bottom portionshowing the bottom structure in still another embodiment of thisinvention.

FIG. 8 is a partially enlarged sectional view of the second check valvein another embodiment of this invention.

FIG. 9 is a partially enlarged sectional view of the second check valvein another embodiment of this invention.

FIG. 10 is a partially enlarged sectional view of the second check valvein another embodiment of this invention.

FIG. 11 is a partially enlarged sectional view of the second check valvein another embodiment of this invention.

FIG. 12 is a partially enlarged sectional view of the second check valvein another embodiment of this invention.

PREFERRED EMBODIMENTS OF THE INVENTION

This invention is further described with respect to the preferredembodiments of this invention, now referring to the drawings.

FIG. 1 is an entire side view of the discharge container in oneembodiment of this invention, with the comb attachment 33 being fittedto the container. The discharge container comprises the squeezablecontainer 1 and the base cup 20, which has been screwed on, and fittedtightly around, the bottom cylinder 8 of this squeezable container 1.The comb attachment 33 is fitted to the neck 6 of the container 1 by wayof a connecting unit 29 in the state in which the internal passage 37 isconnected to the neck 6.

The container 1 has a laminated structure in which the outer layer 2 islaminated with the inner layer 3. The outer layer 2 is capable ofelastic deformation when it is squeezed, and is recoverable from suchdeformation. The inner layer 3 is made of a synthetic resin that is lesscompatible with, and peelable from, the outer layer 2, and is free todeform in response to the reduced amount of the contents. The neck 6 inthe shape of a short cylinder is disposed in the upper portion of thebody 4 by way of the shoulder 5. A spiral thread ridge is carved on theouter peripheral surface of this neck 6. In order to ensure that thecontents can be discharged steadily, it is preferred that at least anadhered strip with a certain narrow width is disposed in the axialdirection from neck to bottom. More preferably, two such strips aredisposed at symmetric positions.

At the lower end of the body 4 there is the bottom cylinder 8 withclosed bottom. The bottom cylinder 8 comprises the peripheral bottomwall 9 and the container bottom plate 13 (See FIG. 2). The peripheralbottom wall 9 is provided with the spiral thread ridge 10, the loweroverhang 11, and the first seal 12. The container bottom plate 13 isprovided with the pinch-off portion 14 that has been formed in the outerlayer 2 by the blow-molding tool at the time when the squeezablecontainer 1 was blow-molded. This pinch-off portion 14 is opened to forman opening 15.

The spiral thread ridge 10 on the bottom cylinder 8 is in itself aperipheral projecting ridge that has been obtained by locallycorrugating the peripheral bottom wall 9, and gives strong shape-holdingpower. In the embodiments shown in FIGS. 2 and 5, the lower overhang 11is disposed below the thread ridge 10. However, the lower overhang 11may be disposed above the thread ridge 10, as shown in FIG. 7.

The first seal 12 is disposed near by this overhang 11. In theembodiment shown in FIG. 2, the first seal 12 is integrated with theoverhang 11 and gives a peripheral ridge structure. In the embodimentshown in FIG. 5, the first seal 12 has a smooth wall structure, and islocated between the spiral thread ridge 10 and the lower overhang 11. Inthe embodiment shown in FIG. 7, the first seal 12 has a smooth wallstructure, and is located between the upper overhang 7 and the loweroverhang 11. In all cases, the first seal 12 is combined with a portionthat serves as a reinforcing rib, and has a stable and strongshape-holding structure.

As shown in FIG. 3, the opening 15 is formed along the parting line atthe pinch-off portion 14 in the outer layer 2 of the container bottomplate 13. This pinch-off portion 14 is opened by acting the pinchingforce on the bottom plate 13 along the parting line. Thus, the pinch-offportion 14 in the molded state shown in FIG. 4(a) is forced to open, asshown in FIG. 4(b).

If the opening 15 was formed as a bottom crack by opening the pinch-offportion 14, the bottom cylinder 8 would naturally have the decreasedmechanical strength because of the crack in the bottom cylinder 8. Butsince the base cup 20 is screwed on, and fitted around, the bottomcylinder 8 to serve as an outer shell, the base cup 20 makes up for anydecreased mechanical strength, and thus, the discharge container canstably stand upright.

The first check valve 18 (See FIG. 1) is fitted tightly to the mouth ofthe neck 6, and in that state, the valve body 19 is disposed at thecentral opening 17 that has been set up in the center of this inner lidgasket 16. This valve body 19 is actuated to open or close the centralopening 17.

The base cup 20 has a bottomed cylindrical shape, in which the cupbottom plate 24 is disposed at the lower end of the cylindrical wall 21,and is fitted around the bottom cylinder 8 in the screw engagement. Aspiral thread ridge 22 is carved on the inner cylindrical wall 21 of thebase cup 20 and is engaged with the corresponding spiral thread ridge10. The second seal 23 is formed at a position opposite the first seal12, and is in tight contact therewith. The air intake hole 25 is openedin the center of the cup bottom plate 24.

In the embodiment shown in FIG. 2, the second seal 23 has a smooth wallstructure. In the embodiment shown in FIG. 5, the second seal 23 has aperipheral ridge structure. And in the embodiment shown in FIG. 7, ithas a structure comprising a combination of plural, small projectingridges. In all the embodiments described above, the second seal 23 isintegrated with the cylindrical wall of the base cup 20. Alternatively,either one of the first seal 12 or the second seal 23 may be made of aring-like elastic material, such as an O-ring (Not shown), which isfixed to the peripheral bottom wall 9 of the container bottom cylinder 8or to the inner surface of the cylindrical wall 21 of the base cup 20,or may be made of a sealing member having elastically deformable feetthat are pressed to either wall. In such a case, tight contact betweenthe first seal 12 and the second seal 23 can be strengthened andstabilized by utilizing the resilient deforming force of the ring-likeelastic member.

The second check valve 27 is fitted to the air intake hole 25 of thebase cup 20. In the embodiments of FIGS. 2, 5, and 7, a valve supportcylinder 26 is disposed on the cup bottom plate 24 so as to surround theair intake hole 25. The valve body 28 is held inside this valve supportcylinder 26 to open or close the air intake hole 25.

The structure of this second check valve 27 is not limited to thatdescribed above. As shown in FIGS. 8 and 9, the valve support cylinder26 with a top plate is disposed in the center of the cup bottom plate24. In one more structure, the air intake hole 25 is opened along theinner wall of this valve support cylinder 26, and the second check valve27 is fitted to the valve support cylinder 26 so that a ring-shapedvalve body 28 covers, and open or close, the air intake hole 25. Inanother structure, the air intake hole 25 is opened in the top plate ofthe valve support cylinder 26, and the second check valve 27 having thisair intake hole 25 opened or closed by the valve body 28 may be fittedinto the valve support cylinder 26, as shown in FIG. 10.

In addition, as shown in FIG. 11, the second check valve 27 shown inFIG. 8 may have a valve support cylinder 26, which is provided with itsown bottom. In still another structure, the second check valve 27 maynot have any valve support cylinder 26 as shown in FIG. 12, but may haveplural cuts along the edge of the air intake hole 25. These cuts are notsealed but are engaged with the periphery of the air intake hole 25 sothat the second check valve 27 allows the valve body 28 to cover theentire air intake hole 25 including the cuts, and enables these cuts tobe used as a practical air intake hole 25.

Connecting unit 29 is used to connect a comb attachment 33 to thesqueezable container 1. This unit 29 comprises a screwing cylinder 30 tobe screwed on the neck 6. A connecting cylinder 32 to be connected tothe neck 6 stands in the center of a flat ring surface 31 disposed atthe upper end of the screwing cylinder 30. Through the screw engagementwith the neck 6, the connecting unit 29 ensures that inner lid gasket 16is fitted into the neck 6, and also ensures that the first check valve18 is fitted to the inner lid gasket 16.

The comb attachment 33 comprises the comb-back 35 that forms the mainpassage 37 through which the contents flow after having been dischargedfrom the container 1; plural teeth 34, which are disposed straight in arow on one side of the comb-back 35 at equal intervals; and a fittingcylinder 36, which is suspended at the lower end of the comb-back 35 andis fitted tightly into the connecting cylinder 32 of the connecting unit29. A pair of discharge ports 39 is disposed at a half height of eachtooth, except for the uppermost tooth and the lowermost tooth. Eachdischarge port 39 is connected to the main passage 37 by way of adischarge path 38.

In the case of the embodiment shown in FIG. 1, a skirt-like cylinderwidening toward the hem is disposed at the lower end of the comb-back 35in such a way that the skirt covers the fitting cylinder 36. Thiscone-shaped cylinder is fitted around the wall that surrounds the flatring surface 31, and thus strengthens and stabilizes the fitting of thecomb attachment 33 to the connecting unit 29.

The comb attachment 33 may be fitted directly to the container 1 withoututilizing any connecting unit 29. However, in that case, direct fittingof the comb attachment 33 to the container 1 should be strong enough tosecure the tight fitting of the inner lid gasket 16 to the neck 6 andthe stable fitting of the first check valve 18 to the inner lid gasket16.

In the case of the embodiment shown in FIG. 1, plural teeth 34 are inthe shape of a one-sided comb and are disposed straight in a row atequal intervals on one side of the comb-back 35 that forms the mainpassage 37 through which the contents flow after having been dischargedfrom the container 1. The comb is not limited to the shape of thisembodiment, but may have the shape of a both-sided comb in which theteeth are disposed at equal intervals on both sides of the comb-back 35,or may be in the shape of a brush in which two or more rows of teeth 34are disposed widely on one side.

When the body 4 of the container 1 is squeezed, the inside of the innerlayer 3 is always pressurized whatever direction the comb attachment 33is aimed at. Since the first check valve 18 is actuated under thepressurized condition to open the neck 6, the contents such as a hairdye product flow through the main passage 37 and the discharge path 38,and are discharged from the discharge ports 39 into the spaces betweenthe teeth. Then, the hair dye is applied onto the hair by combing thehair with the comb teeth 34.

As soon as the body 4 is released from the squeeze, the pressurizedinside of the inner layer 3 falls into a reduced pressure condition, andthe first check valve 18 is closed, thus preventing outside air and thedischarged contents from flowing inside the inner layer 3.

When the body 4 is released from the squeeze, the outer layer beginsrestoring its original shape owing to the resilient recovery force. Butsince outside air does not enter the container 1 due to the work of thefirst check valve 18, the inner layer 3 remains deflated after it hasbeen broken away from the outer layer 2, and the interspace between theouter layer 2 and the inner layer 3 is put under a negative pressurecondition.

As a result, the second check valve 27 opens, and outside air passesthrough the air intake hole 25 of the base cup 20 and through theopening 15 of the container 1 into the interspace between the outerlayer 2 and the inner layer 3. The outer layer 2 returns to its originalshape.

Outside air is confined in the interspace between the outer layer 2 andthe inner layer 3 when the second check valve 27 goes back to the closedstate. If the body 4 of the container 1 is squeezed again under thiscondition, the inner layer 3 is pressurized, and the contents aredischarged from the container 1.

EFFECTS OF THE INVENTION

This invention having the above-described configuration has thefollowing effects:

In the invention of Claim 1, the base cup is fitted around the container1 by the screw engagement. Even if the container 1 has highsqueezability, the fitting strength between the base cup and thecontainer never decreases. This fitting enables the resources saving tobe accomplished. At the same time, it is possible to enhance thesqueezability safely and to increase the easiness to use the container.

The container is provided with the first seal, which comes in tightcontact with the second seal of the base cup. This contact ensures thatthe base cup is kept in tight contact with the bottom cylinder of thecontainer.

In the invention of Claim 2, the first seal is disposed at a positionnear the lower overhang that serves as reinforcement. Even if thecontainer has high squeezability, the overhang gives strength enough tokeep the shape of the first seal. Thus, the tight fitting between thebase cup and the bottom cylinder of the container can be maintainedsecurely and firmly.

In the invention of Claim 3, an opening is formed by cleaving thepinch-off portion that has been formed in the outer layer along theparting line. The bottom is easily cleaved because of the laminatedstructure of the outer layer and the inner layer, which are notcompatible with each other. The crack can be utilized as it is, andthere is no need of troublesome molding operation and equipment forobtaining an opening.

In the invention of Claim 4, the sealing portions comprise a combinationof a peripheral projecting ridge structure and a smooth peripheral wallstructure. Because of such a simple configuration, the sealing portionscan be properly molded by the blow molding method.

In the invention of Claim 5, the first seal comes in tight contact withthe second seal by means of an elastic ring-shaped material. Theresilient deforming force of this material can be utilized to make thetight contact strong and stable.

In the invention of Claim 6, the comb attachment is fitted to thecontainer in such a way that the contents inside the container can bedischarged into the spaces between plural teeth that have been alignedin a row. The user can squeeze out the contents directly into the spacesbetween the teeth, and can continuously apply the contents onto thehair, using this comb. Therefore, application of a hair dye onto thehair can be accomplished efficiently and favorably.

1. A discharge container comprising: a squeezable container, which hasan outer layer and an inner layer that are laminated to each other in apeelable manner, a neck disposed in the upper portion of said containerand connected to discharge ports through which the contents aredischarged, and an opening disposed in a part of said outer layer at aposition in the bottom plate of container bottom cylinder so as tointroduce outside air into the interspace between said outer layer andthe inner layer; the first check valve, which opens or closes said neckto prevent the contents from flowing back into said container and toinhibit the inflow of outside air; a base cup in a bottomed cylindricalshape, which has a cylindrical wall that comes in screw engagement withsaid container bottom cylinder and also has an air intake hole opened incup bottom plate; and a second check valve fitted to said air intakehole to permit outside air to enter the interspace between layers,wherein airtight fitting of peripheral bottom wall to the cylindricalwall is accomplished by tight contact between the first seal disposed onsaid peripheral bottom wall of the bottom cylinder and the second sealdisposed on the back of said cylindrical wall.
 2. The dischargecontainer according to claim 1, wherein lower overhang is disposed onthe peripheral bottom wall of the bottom cylinder of the container andwherein the first seal is disposed at a position near this loweroverhang.
 3. The discharge container according to claim 1, wherein anopening is formed by cleaving a pinch-off portion that has been formedin the outer layer of said container bottom plate.
 4. The dischargecontainer according to claim 1 wherein either the first seal or thesecond seal has a peripheral projecting ridge structure, with the otherhaving a smooth wall structure.
 5. The discharge container according toclaim 1 wherein either the first seal or the second seal is made of anelastic material in the shape of a ring, and is fitted to the peripheralbottom wall of the container bottom cylinder or to the cylindrical wallof the base cup.
 6. The discharge container according to claim 1 whereina comb attachment is fitted to neck, with said comb attachmentcomprising a row of combing teeth supported in a line on the comb-backhaving an internal main passage that connects to the neck of thecontainer, and each tooth having front and rear discharge ports openedat a halfway point of the tooth height in the longitudinal direction ofteeth and disposed face to face with opposite discharge ports of thenext teeth, and each tooth also having a discharge path that connectssaid discharge ports to the main passage.